The Autonomic Nervous System S. J. Potashner

Autonomic NS A division of the nervous system Innervates & regulates effectors of homeostasis Cardiovascular organs Respiratory organs Digestive organs Urinary organs Reproductive organs Glands Part of a network of structures in the CNS

Autonomic NS Three major subdivisions Sympathetic division: organized to mobilize the body for activity Parasympathetic division: organized for energy conservation Enteric division: controls the local functions of the GI tract

Lower Motor Pathways

Sympathetic Pathways

X-Section Upper Abdomen Ant Post RL

Parasympathetic Pathways

Autonomic Pathways

Sympathetic Division Parasympathetic Division Mobilize body for activity: Energy expenditure Decrease energy stores Catabolic functions Cardio-pulmonary adjustments Energy conservation: Reduce energy expenditure Increase energy stores Anabolic functions Cardio-pulmonary adjustments Functions

ActionsSympParasymp Breathing rate+- Bronchodilation+- Heart rate & output+- Blood pressure+0 Skeletal muscle vasodilation+ GI blood flow-+ Digestion-+ Glycogenolysis & glucose release from liver+0 Insulin secretion-+ Fat & glycogen synthesis & storage-+ Pupillary dilation+0 Pupillary constriction0+ Sweating+0 Functions

Baroreflex Carotid body Cardiac plexus SA node Glossopharyngeal n. Vagus n. NTS Nucleus ambiguus (-)(-) (-)(-) (-)(-) (+)(+) T1-T5 Heart rate & contraction increase Cardiac n. Excitatory Inhibitory

Baroreflex Carotid body Cardiac plexus SA node Glossopharyngeal n. Vagus n. NTS Nucleus ambiguus (+) (+)(+) (+)(+) (-)(-) T1-T5 Heart rate & contraction decrease Cardiac n. Excitatory Inhibitory

Bladder Control T10-L2 S2-S4 Bladder Urethra Internal urethral sphincter (males) External urethral sphincter Detrusor muscle Sympathetic Parasympathetic Somatic motor Sensory